Project 1: Digital I/O and Timing

All components of the project are due by February 26th at 5:00pm.
Two person groups are required

Project Goals

At the end of this project, you should be able to:

Create, compile, and download code to the Atmel Mega8,
Manipulate digital I/O lines, and
Use the internal timers/interrupts to produce regularly timed events.

Project Components

Part 1

Implement an internal 4-bit counter (use a variable of type uint8_t).
The state of the counter is indicated using 4 LED channels:
- Bit 0: Yellow
- Bit 1: Blue
- Bit 2: Red
- Bit 3: Green
Each time the button is released, the counter should be incremented. Incrementing the counter from 0xf should result in a value of 0.

Part 2

Produce a musical tone using the speaker. Tones can be produced by turning the speaker "on" and "off" at some frequency.
The frequency of the tone should decrease with higher counter values. (alternatively, you could play one bar of Yankee Doodle with each counter value)

Things You Should Know

We are using the bion boards for this project (so there is no hardware development).

There are three debugging LEDs (red, green, and yellow) attached to PORTB, pins 0, 1, 2
The blue LEDs are all attached to PORTC, pin 5
The piezoelectric speaker is attached to PORTD, pin 2
Switch 1 is the reset switch (pushing it will cause the processor to reboot)
Switch 2 is attached to PORTD, pin 3. This pin will read 1 when the button is not pressed and 0 when it is pressed.

Note: you should only configure the LED and speaker pins as outputs. All other pins should be configured as inputs (otherwise, you can damage the chip).

References:

Atmel HOWTO
Frequencies of musical tones. Note that you will only be able to approximate these frequencies

Implementation Notes

Modularize your code: keep routines simple. For example, you should separate the counting process from the LED state changes. In particular, we expect you to implement a DisplayCounter() function that is responsible for updating the state of the LEDs

What to Hand In

All components of the project are due by February 26th at 5:00pm.

Group report: Turn in your documented code to the project 1 digital dropbox on D2L (text format). Only hand in one copy of code per 2-person group.
Group demonstration: Demonstrate your working implementation to either a TA or the instructor). This demonstration is due at the same time as the reports. All group members must be present for the demonstration.
Personal report: State the relative contribution of you and your partner (in terms of percentage of effort) (short and in text format)

Grading

50%: Project implementation
25%: Demonstration of working project
25%: Internal documentation of the code

fagg [[at]] ou.edu

Last modified: Wed Feb 13 22:17:16 2008